Development of immunoassay for detection of meat and bone meal in animal feed

The Development of a Risk Assessment Model for Inedible Rendering Plants in Canada: Identifying and Selecting Feed Safety-Related Factors

The Canadian Food Inspection Agency (CFIA) is developing an establishment-based risk assessment model to categorize rendering plants that produce livestock feed ingredients (ERA-Renderer model) according to animal and human health risks (i.e., feed safety risks) and help in determining the allocation of inspection resources based on risk. The aim of the present study was to identify and select feed-safety-related factors and assessment criteria for inclusion in the ERA-Renderer model. First, a literature review was performed to identify evidence-based factors that impact the feed safety risk of livestock feed during its rendering processes. Secondly, a refinement process was applied to retain only those that met the inclusion conditions, such as data availability, lack of ambiguity, and measurability. Finally, an expert panel helped in selecting factors and assessment criteria based on their knowledge and experience in the rendering industry. A final list of 32 factors was developed, of which 4 pertained to the inherent risk of a rendering plant, 8 were related to risk mitigation strategies, and 20 referred to the regulatory compliance of a rendering plant. A total of 179 criteria were defined to assess factors based on practices in the Canadian rendering industry. The results of this study will be used in the next step of the model development to estimate the relative risks of the assessment criteria considering their impact on feed safety. Once implemented, the CFIA's ERA-Renderer model will provide an evidence-based, standardized, and transparent approach to help manage the feed safety risks in Canada's rendering sector.

A novel multiplex xMAP assay for generic detection of avian, fish, and ruminant DNA in feed and feedstuffs

The identification of animal species in feed and feedstuffs is important for detecting contamination and fraudulent replacement of animal components that might cause health and economic problems. A novel multiplex assay, based on xMAP technology and the generic detection of closely related species, was developed for the simultaneous differential detection of avian, fish, and ruminant DNA in products. Universal primers and probes specific to avian, fish, or ruminant species were designed to target a conserved mitochondrial DNA sequence in the 12S ribosomal RNA gene (rRNA). The assay specificity was validated using samples of 27 target and 10 nontarget animal species. The limits of detection of the purified DNA were determined to be 0.2 pg/μL-0.1 ng/μL by testing the meat samples of six species and four feedstuffs. The detection sensitivity of the experimental mixtures was demonstrated to be 0.01% (weight percentage). The assay's suitability for practical application was evaluated by testing feed samples; unlabeled animal ingredients were detected in 32% of the 56 samples. The assay differentially detected the three targeted categories of animal species in less than 2 h, reflecting improvements in speed and efficiency. Based on these results, this novel multiplex xMAP assay provides a reliable and highly efficient technology for the routine detection of animal species in feed and other products for which this information is needed.

Practices and exploration on competition of molecular biological detection technology among students in food quality and safety major

With the increasing importance in the application of the molecular biological detection technology in the field of food safety, strengthening education in molecular biology experimental techniques is more necessary for the culture of the students in food quality and safety major. However, molecular biology experiments are not always in curricula of Food quality and safety Majors. This paper introduced a project "competition of molecular biological detection technology for food safety among undergraduate sophomore students in food quality and safety major", students participating in this project needed to learn the fundamental molecular biology experimental techniques such as the principles of molecular biology experiments and genome extraction, PCR and agarose gel electrophoresis analysis, and then design the experiments in groups to identify the meat species in pork and beef products using molecular biological methods. The students should complete the experimental report after basic experiments, write essays and make a presentation after the end of the designed experiments. This project aims to provide another way for food quality and safety majors to improve their knowledge of molecular biology, especially experimental technology, and enhances them to understand the scientific research activities as well as give them a chance to learn how to write a professional thesis. In addition, in line with the principle of an open laboratory, the project is also open to students in other majors in East China University of Science and Technology, in order to enhance students in other majors to understand the fields of molecular biology and food safety. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):343-350, 2017.

Peptidomic Approach to Developing ELISAs for the Determination of Bovine and Porcine Processed Animal Proteins in Feed for Farmed Animals

The European Commission (EC) wants to reintroduce nonruminant processed animal proteins (PAPs) safely into the feed chain. This would involve replacing the current ban in feed with a species-to-species ban which, in the case of nonruminants, would only prohibit feeding them with proteins from the same species. To enforce such a provision, there is an urgent need for species-specific methods for detecting PAPs from several species in animal feed and in PAPs from other species. Currently, optical microscopy and the polymerase chain reaction are the officially accepted methods, but they have limitations, and alternative methods are needed. We have developed immunoassays using antibodies raised against targets which are not influenced by high temperature and pressure. These targets were identified in a previous study based on an experimental approach. One optimized competitive ELISA detects bovine PAPs at 2% in plant-derived feed. The detection capability demonstrated on blind samples shows a good correlation with mass spectrometry results.

Species Identification of Bovine, Ovine and Porcine Type 1 Collagen; Comparing Peptide Mass Fingerprinting and LC-Based Proteomics Methods

Collagen is one of the most ubiquitous proteins in the animal kingdom and the dominant protein in extracellular tissues such as bone, skin and other connective tissues in which it acts primarily as a supporting scaffold. It has been widely investigated scientifically, not only as a biomedical material for regenerative medicine, but also for its role as a food source for both humans and livestock. Due to the long-term stability of collagen, as well as its abundance in bone, it has been proposed as a source of biomarkers for species identification not only for heat- and pressure-rendered animal feed but also in ancient archaeological and palaeontological specimens, typically carried out by peptide mass fingerprinting (PMF) as well as in-depth liquid chromatography (LC)-based tandem mass spectrometric methods. Through the analysis of the three most common domesticates species, cow, sheep, and pig, this research investigates the advantages of each approach over the other, investigating sites of sequence variation with known functional properties of the collagen molecule. Results indicate that the previously identified species biomarkers through PMF analysis are not among the most variable type 1 collagen peptides present in these tissues, the latter of which can be detected by LC-based methods. However, it is clear that the highly repetitive sequence motif of collagen throughout the molecule, combined with the variability of the sites and relative abundance levels of hydroxylation, can result in high scoring false positive peptide matches using these LC-based methods. Additionally, the greater alpha 2(I) chain sequence variation, in comparison to the alpha 1(I) chain, did not appear to be specific to any particular functional properties, implying that intra-chain functional constraints on sequence variation are not as great as inter-chain constraints. However, although some of the most variable peptides were only observed in LC-based methods, until the range of publicly available collagen sequences improves, the simplicity of the PMF approach and suitable range of peptide sequence variation observed makes it the ideal method for initial taxonomic identification prior to further analysis by LC-based methods only when required.

Protein and mineral characterisation of rendered meat and bone meal

We report the characterisation of meat and bone meal (MBM) standards (Set B-EFPRA) derived from cattle, sheep, pig and chicken, each rendered at four different temperatures (133, 137, 141 and 145 °C). The standards, prepared for an EU programme STRATFEED (to develop new methodologies for the detection and quantification of illegal addition of mammalian tissues in feeding stuffs), have been widely circulated and used to assess a range of methods for identification of the species composition of MBM. The overall state of mineral alteration and protein preservation as a function of temperature was monitored using small angle X-ray diffraction (SAXS), amino acid composition and racemization analyses. Progressive increases in protein damage and mineral alteration in chicken and cattle standards was observed. In the case of sheep and pig, there was greater damage to the proteins and alteration of the minerals at the lowest treatment temperature (133 °C), suggesting that the thermal treatments must have been compromised in some way. This problem has probably impacted upon the numerous studies which tested methods against these heat treatments. We use protein mass spectrometric methods to explore if thermostable proteins could be used to identify rendered MBM. In more thermally altered samples, so-called 'thermostable' proteins such as osteocalcin which has been proposed as a ideal target to speciate MBM were no longer detectable, but the structural protein type I collagen could be used to differentiate all four species, even in the most thermally altered samples.

Authentication of meat and meat products

In recent years, interest in meat authenticity has increased. Many consumers are concerned about the meat they eat and accurate labelling is important to inform consumer choice. Authentication methods can be categorised into the areas where fraud is most likely to occur: meat origin, meat substitution, meat processing treatment and non-meat ingredient addition. Within each area the possibilities for fraud can be subcategorised as follows: meat origin-sex, meat cuts, breed, feed intake, slaughter age, wild versus farmed meat, organic versus conventional meat, and geographic origin; meat substitution-meat species, fat, and protein; meat processing treatment-irradiation, fresh versus thawed meat and meat preparation; non-meat ingredient addition-additives and water. Analytical methods used in authentication are as diverse as the authentication problems, and include a diverse range of equipment and techniques. This review is intended to provide an overview of the possible analytical methods available for meat and meat products authentication. In areas where no authentication methods have been published, possible strategies are suggested.

Species identification by analysis of bone collagen using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry

Species identification of fragmentary bone, such as in rendered meat and bone meal or from archaeological sites, is often difficult in the absence of clear morphological markers. Here we present a robust method of analysing genus-specific collagen peptides by mass spectrometry simply by using solid-phase extraction (a C18 ZipTip) for peptide purification, rather than liquid chromatography/mass spectrometry (LC/MS). Analysis of the collagen from 32 different mammal species identified a total of 92 peptide markers that could be used for species identification, for example, in processed food and animal feed. A set of ancient (>100 ka@10 degrees C) bone samples was also analysed to show that the proposed method has applications to archaeological bone identification.